You provide no evidence or logical reasoning as to why the Abram's is superior to the latest Chinese Type-99 apart from that "US technology is superior".
China could have purchased T-90 tanks from Russia in the 1990s but chose not to. Only logical reason is that they were pretty happy with their own technology. Whether the Abrams may be slightly superior to the Chinese tank is irrelevant as they both pretty much have the ability to take each other out with one hit IMO.
Yes, they will. China has thousands of ballistic and cruise missiles that would severely the Japanese military and industrial facilities without their airforce even getting involved.
And even the US carriers will have to stay further out from the Chinese coast(several hundred kms) as they would not be wishing to face hundreds of J-20s and J-31s that could operate from Chinese land bases, not to mention the DF-21D ASBM.
Basically Japan would then be the theatre where the Chinese and US fight it out and it would be devastated as you can be sure if the Japanese ask the US for help then China would take revenge on them in a devastating way.
Yes they will. Time is on China's side.
India will never be any kind of match for China in our lifetime, if ever.
A coalition of smaller states against a country like China, which most experts predict to overtake US in GDP by the latter part of this decade, just won't work in practice. They will all learn to accept Chinese dominance over east Asia, and maybe rest of Asia later on. Even Japan would have to submit to the inevitable, let alone countries like South Korea and Taiwan - btw Taiwan is just a province of China and not a real country.
Let the US spend trillions on building a Navy to retain "dominance" when the best thing to do is for the US to accept the inevitable and retreat to the continental US and spend the saved money on their civilian economy rather than this soon to be useless expeditionary military.
Unlike Europe, which is pretty much finished, the US has a future but it does not seem to be playing it's cards right. It is up to you but interfering in Asia won't turn out well for you in the end